Modern electrochemical techniques are being used in three areas of adrenergic neurochemistry. First, we are examining the oxidative interactions of catecholamines and neurotoxins like 6-hydroxydopamine. Such studies are aimed as uncovering molecular mechanisms of neurotoxic action. Secondly, using micro electrodes we are studying the in vivo electrochemistry of catecholamines, their metabolites and various drugs affecting adrenergic systems. Measurements can be made concerning the fate of injected drugs by continuous voltammetric monitoring in brain tissue. The use of these electrodes in lateral ventricle allows one to follow the release of transmitter metabolites into the CSF following electrical stimulation of known neural pathways. Thirdly, a sensitive electrochemical detector has been mated to high performnce liquid chromatography. Rapid, accurate analyses of dopamine, norepinephrine, their acidic metabolites and ascorbate have been developed. Analyses of dopamine and norepinephrine in the low picogram level are routine and these are being applied to a variety of neurochemical analysis problems.